The Hancock air whistle was a railroad whistle

Whistle

A whistle or call is a simple aerophone, an instrument which produces sound from a stream of forced air. It may be mouth-operated, or powered by air pressure, steam, or other means...

 intended for use on North America

North America

North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...

n diesel locomotive

Diesel locomotive

A diesel locomotive is a type of railroad locomotive in which the prime mover is a diesel engine, a reciprocating engine operating on the Diesel cycle as invented by Dr. Rudolf Diesel...

s in place of the standard air horn

Train horn

Train horns are audible warning devices found on most diesel and electric locomotives. Their primary purpose is to alert persons and animals to the presence of a train, especially when approaching a grade crossing. They are also used for acknowledging signals given by railroad employees Train horns...

.

History

Hancock was a familiar name to railroads during the days of steam

Steam locomotive

A steam locomotive is a railway locomotive that produces its power through a steam engine. These locomotives are fueled by burning some combustible material, usually coal, wood or oil, to produce steam in a boiler, which drives the steam engine...

. The company produced many appliances, one of which was the popular long-bell three-chime steam whistle

Steam whistle

A steam whistle is a device used to produce sound with the aid of live steam, which acts as a vibrating system .- Operation :...

. When railroads began dieselising

Dieselisation

Dieselisation or dieselization is a term generally used for the increasingly common use of diesel fuel in vehicles, as opposed to gasoline or steam engines.-Water Transport:...

, Hancock, along with other manufacturers of railroad equipment, adjusted their offerings in order to remain competitive. And so Hancock modified their whistle design so they could be used on diesel locomotives.

Hancock already had vast experience with whistles, and practically none with horns. Also, diesel locomotives were an emerging technology, and most early models were equipped with single-note 'honkers'. These horns were anything but appealing to the general public. Therefore, Hancock developed their line of air whistles in an attempt to romanticize

Romanticism

Romanticism was an artistic, literary and intellectual movement that originated in the second half of the 18th century in Europe, and gained strength in reaction to the Industrial Revolution...

 the diesel locomotives.

Production of these air whistles spanned from the late 1950s until the late 1960s.

The New York, New Haven and Hartford Railroad

New York, New Haven and Hartford Railroad

The New York, New Haven and Hartford Railroad , was a railroad that operated in the northeast United States from 1872 to 1968 which served the states of Connecticut, New York, Rhode Island, and Massachusetts...

 was a large user of these whistles, and every FL9

EMD FL9

The EMD FL9 was a dual-power electro-diesel locomotive, capable of diesel-electric operation and of operation as an electric locomotive powered from a third rail...

 purchased by the New Haven came from the factory equipped with a Hancock air whistle on the roof. Unfortunately, it was found that at high speeds, the whistles were difficult to hear. Class I railroads eventually replaced their Hancock whistles with horns, namely for safety reasons. There are, however, short line railroads which continue to use these whistles.

Types of air whistles

Hancock offered three different models of their air whistle. The most common was the 4700, which consisted of the whistle along with a large, rectangular bowl in the same plane as the languid plate. This bowl, or reflector

Reflector

-Science:* Reflector, a device that causes reflection * Reflector , used to control lighting contrast* Reflecting telescope* Reflector , the part of an antenna that reflects radio waves...

, is used to project the sound of the whistle ahead of the locomotive, instead of omnidirectional

Omnidirectional

Omnidirectional refers to the notion of existing in every direction. Omnidirectional devices include:* Omnidirectional antenna, an antenna that radiates equally in all directions* VHF omnidirectional range, a type of radio navigation system for aircraft...

 as in the case of most whistles. The second model was the 4700-2. This whistle is basically the same as the 4700 except that it has an electric heating element installed in the bowl to keep it from freezing. The final offering was the H4700, which did not include the reflector bowl. Aside from this difference, it is basically identical to the 4700.

The Hancock air whistles were all designed so that the bell of the whistle is horizontal when mounted on a standard horn mount. All the whistles are a single-bell chime, playing the notes E A C# (A major triad) when blown on air. However, over time, many of the whistles got off-key and produced some variants. One common chord

Chord (music)

A chord in music is any harmonic set of two–three or more notes that is heard as if sounding simultaneously. These need not actually be played together: arpeggios and broken chords may for many practical and theoretical purposes be understood as chords...

was E A D.

Audio samples

• Hancock 4700 air whistle